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-rw-r--r--net/mptcp/crypto.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/net/mptcp/crypto.c b/net/mptcp/crypto.c
new file mode 100644
index 000000000000..bbd6d01af211
--- /dev/null
+++ b/net/mptcp/crypto.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Multipath TCP cryptographic functions
+ * Copyright (c) 2017 - 2019, Intel Corporation.
+ *
+ * Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and
+ * mptcp_ipv6 from multipath-tcp.org, authored by:
+ *
+ * Sébastien Barré <sebastien.barre@uclouvain.be>
+ * Christoph Paasch <christoph.paasch@uclouvain.be>
+ * Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
+ * Gregory Detal <gregory.detal@uclouvain.be>
+ * Fabien Duchêne <fabien.duchene@uclouvain.be>
+ * Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
+ * Lavkesh Lahngir <lavkesh51@gmail.com>
+ * Andreas Ripke <ripke@neclab.eu>
+ * Vlad Dogaru <vlad.dogaru@intel.com>
+ * Octavian Purdila <octavian.purdila@intel.com>
+ * John Ronan <jronan@tssg.org>
+ * Catalin Nicutar <catalin.nicutar@gmail.com>
+ * Brandon Heller <brandonh@stanford.edu>
+ */
+
+#include <linux/kernel.h>
+#include <linux/cryptohash.h>
+#include <asm/unaligned.h>
+
+#include "protocol.h"
+
+struct sha1_state {
+ u32 workspace[SHA_WORKSPACE_WORDS];
+ u32 digest[SHA_DIGEST_WORDS];
+ unsigned int count;
+};
+
+static void sha1_init(struct sha1_state *state)
+{
+ sha_init(state->digest);
+ state->count = 0;
+}
+
+static void sha1_update(struct sha1_state *state, u8 *input)
+{
+ sha_transform(state->digest, input, state->workspace);
+ state->count += SHA_MESSAGE_BYTES;
+}
+
+static void sha1_pad_final(struct sha1_state *state, u8 *input,
+ unsigned int length, __be32 *mptcp_hashed_key)
+{
+ int i;
+
+ input[length] = 0x80;
+ memset(&input[length + 1], 0, SHA_MESSAGE_BYTES - length - 9);
+ put_unaligned_be64((length + state->count) << 3,
+ &input[SHA_MESSAGE_BYTES - 8]);
+
+ sha_transform(state->digest, input, state->workspace);
+ for (i = 0; i < SHA_DIGEST_WORDS; ++i)
+ put_unaligned_be32(state->digest[i], &mptcp_hashed_key[i]);
+
+ memzero_explicit(state->workspace, SHA_WORKSPACE_WORDS << 2);
+}
+
+void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
+{
+ __be32 mptcp_hashed_key[SHA_DIGEST_WORDS];
+ u8 input[SHA_MESSAGE_BYTES];
+ struct sha1_state state;
+
+ sha1_init(&state);
+ put_unaligned_be64(key, input);
+ sha1_pad_final(&state, input, 8, mptcp_hashed_key);
+
+ if (token)
+ *token = be32_to_cpu(mptcp_hashed_key[0]);
+ if (idsn)
+ *idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[3]));
+}
+
+void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u32 nonce1, u32 nonce2,
+ u32 *hash_out)
+{
+ u8 input[SHA_MESSAGE_BYTES * 2];
+ struct sha1_state state;
+ u8 key1be[8];
+ u8 key2be[8];
+ int i;
+
+ put_unaligned_be64(key1, key1be);
+ put_unaligned_be64(key2, key2be);
+
+ /* Generate key xored with ipad */
+ memset(input, 0x36, SHA_MESSAGE_BYTES);
+ for (i = 0; i < 8; i++)
+ input[i] ^= key1be[i];
+ for (i = 0; i < 8; i++)
+ input[i + 8] ^= key2be[i];
+
+ put_unaligned_be32(nonce1, &input[SHA_MESSAGE_BYTES]);
+ put_unaligned_be32(nonce2, &input[SHA_MESSAGE_BYTES + 4]);
+
+ sha1_init(&state);
+ sha1_update(&state, input);
+
+ /* emit sha256(K1 || msg) on the second input block, so we can
+ * reuse 'input' for the last hashing
+ */
+ sha1_pad_final(&state, &input[SHA_MESSAGE_BYTES], 8,
+ (__force __be32 *)&input[SHA_MESSAGE_BYTES]);
+
+ /* Prepare second part of hmac */
+ memset(input, 0x5C, SHA_MESSAGE_BYTES);
+ for (i = 0; i < 8; i++)
+ input[i] ^= key1be[i];
+ for (i = 0; i < 8; i++)
+ input[i + 8] ^= key2be[i];
+
+ sha1_init(&state);
+ sha1_update(&state, input);
+ sha1_pad_final(&state, &input[SHA_MESSAGE_BYTES], SHA_DIGEST_WORDS << 2,
+ (__be32 *)hash_out);
+}